Domains for motion is not necessary feature of

Options

A. Paramagnetism
B. Diamagnetism
C. Ferromagnetism
D. Both (1) & (2)

Answer

To solve the question "Domains for motion is not a necessary feature of," we need to analyze the characteristics of the three types of magnetism: diamagnetism, paramagnetism, and ferromagnetism.

### Step-by-Step Solution:

1. **Understanding Diamagnetism**:
- In diamagnetic materials, all the electrons are paired, and their magnetic moments cancel each other out. Thus, the net magnetic moment is zero.
- When an external magnetic field is applied, the electrons align in such a way that they create a magnetic field opposing the external field, leading to a weak repulsion.
- **Conclusion**: No domains are formed in diamagnetic materials.

2. **Understanding Paramagnetism**:
- Paramagnetic materials have unpaired electrons, which means they have a net magnetic moment.
- In the absence of an external magnetic field, these moments are randomly oriented, resulting in no net magnetism.
- When an external magnetic field is applied, the unpaired electrons tend to align with the field, but this alignment is not permanent and does not involve domains.
- **Conclusion**: No domains are formed in paramagnetic materials.

3. **Understanding Ferromagnetism**:
- Ferromagnetic materials have regions called domains, where groups of atoms have their magnetic moments aligned in the same direction.
- In the absence of an external magnetic field, these domains are randomly oriented, but when a magnetic field is applied, the domains can grow in size and align with the field, leading to strong magnetism.
- **Conclusion**: Domains are a necessary feature of ferromagnetic materials.

4. **Final Analysis**:
- From the analysis, we see that diamagnetism and paramagnetism do not require domains for their magnetic properties, while ferromagnetism does.
- Therefore, the answer to the question is that domains for motion are not a necessary feature of **both diamagnetism and paramagnetism**.

5. **Selecting the Correct Option**:
- The correct answer is **option D: both 1 and 2 (diamagnetism and paramagnetism)**.